Slashdot videos: Now with more Slashdot!

View

Discuss

Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

coondoggie writes "The European Space Agency today said it would develop a radar system that will be capable of tracking space hazards such as asteroids and orbital debris. ESA and France's Office National d'Etudes et Recherches Aérospatiales research center will work with five other partners in France, Spain and Switzerland to this month design a test surveillance radar and develop a $6 million demonstrator model."

I say we preemptively nudge a few asteroids into the backside of the moon, just to be on the safe side. NASA's got Dawn out there, we could repurpose it. Vesta and Ceres would make a nice satisfying bang when they hit.

Are you kidding? It said an asteroid tracking radar! This isn't an asteroid-tracking radar or there would have been a hyphen there. I can imagine all sorts of things that the military could use it for like finding the source of broadcast radar pulses and destroying them.

Not as hard as you would think [nasa.gov]. Radar is actually already in (relatively) wide use for asteroid research, since asteroids tend to have quite low albedos (ie., they're really dark) and aren't lit that well. It's often easier to get a radar image than a decent visible image...of course, that's if you already know where the asteroid is and can use a high-gain antenna (like Goldstone's) to not waste all your power.

Venus is visible to the naked eye before the sun even fully sets. Kinda different than an asteroid.

But the main thing is I was implicitly tying "tracking" and "discovery" in my head, since most 'normal' uses of radar the two coincide. Discovering asteroids with radar would be ridiculous. Examining objects already known allows the use of high-gain antennae and so is much more feasible as the AC pointed out.

Given the state of modern RF technology, I wouldn't exclude even that. We can send massive RF pulses today and I think that the best radar interferometers are much more sensitive than any optical telescope we've ever built. The problem might be that most of the larger asteroids have already been found using other means, so studying the known significant ones makes more sense than finding the remaining pebbles.

I was going to come on here and complain about how inefficient radar is, when used at the sort of distances that are common in space. Low and behold the summary is wrong and they plan to use it to track orbital debris which is a much more logical use of a radar system.

But where a radar would come in handy is accurately determining the orbital elements of an asteroid once detected. With infrared telescopes all you get with a detection is the brightness and direction. Successive observations as the asteroid and satellite move over the course of months is required to develop enough data for decent orbit, and if it is one that will come close to

It isn't practical to do this. Radar requires a relatively large investment of energy. GPS signals (by comparison) are extremely weak and low-energy. In other words, GPS systems don't have the power to do it. Nor the size for that matter: radar at these scales requires rather large emitters and receivers, in the scale of 20+ meters. Hard to do that on a GPS satellite (or any satellite, for that matter).

I guess that a (modified version of) SMART-L radar [wikipedia.org] could do this job. Don't understand why 6 milion Euro is needed for building a demonstrator.

Have you read your own link? It says it can track an aircraft at 480 km. Now, assuming that just area is the only concern (and that radar waves are not altered when crossing the ionosphere), an space object with an area of 0.25m^2 (which can easily destroy a rocket/satellite) would be undetectable at just 100km. And that is just the lower limit of "space", and assumes that the radar is vertically under the object.

one of the articles linked in the post does mention asteroids, and in truth, if an asteroid on a collision course or near miss was to intersect the radar signal, you would get several milliseconds, perhaps even a second, of pucker time before the event was over.

Had some fun looking up and finding some more information about the project and why it is being done.Seems that ONERA, the French aerospace research institute, builds military radar among other things, and their bistatic experiment worked so well it is practically a finished product, so they are expanding it already. The OP project is probably based on this. So these things are dual-use though the OP's ESA project says it is to protect satellites and European citizens.Overview of ONERA radar products: http://www.onera.fr/demr-en/references.php [onera.fr]

Details about the French GRAVES experimental bistatic radar facility and how it works with Germany's TIRA.So successful they are being upgraded now. France, Australia and Canada cooperate with the USAF.GRAVES was built in 2004 and is owned by the French arms procurement agency.GRAVES is for objects in Low Earth Orbit, up to 1000km altitude. The upgrade will allow it to broaden the swath of sky and to eliminate errors in trajectory position to more precisely determine on its own whether or not two objects are destined to collide.TIRA belongs to the German military. Though the new system is for all Germany not just the military they say."... Space situational awareness [is seen] as an important element in Germany’s national sovereignty."From 2012, TIRA personnel will be trained by French and Americans.http://www.spacenews.com/military/110531-france-germany-anchor-europe-ssa.html [spacenews.com]

A bit more info on the OP article (French so use Google translate)http://www.smartplanet.fr/smart-technology/un-futur-radar-europeen-contre-les-debris-de-lespace-17211/ [smartplanet.fr] It adds:- work begins Sept. 2012- The goal is to help European satellite operators to exclude collision risk and improve safety in Earth orbit, an area in which France has recognized expertise, says ESA.- "The two demonstrators radar will be part of an initial network of sensors that will also include optical telescopes and data processing centers to ensure observation of space debris on all types of orbits. '- In the case of new experimental radar, the transmitter will be on the influence of the former airbase Crucey-Villages (Eure-et-Loir), about 100 km west of Paris, and the receiver will near Palaiseau (Essonne), south of Paris.- The SSA... first phase, the preparatory program, [was] authorized... in November 2008. As part of this program, the ESA is to acquire the ability to monitor any danger to the area, since the risk of collisions between satellites and space debris to the impact of a celestial body through natural by space weather related to solar activity.- The SSA program exposes the ESA will provide the final of Europe's ability to detect, predict and evaluate the potential risks to life and property represented by space debris, atmospheric reentry, explosions in orbit launches , collisions, disruption of missions and services using satellites, the potential impacts of NEOs, and the effects of intense space weather events on infrastructure both space and on the ground.- In summer 2011, a U.S. report had alerted the critical level of waste in orbit . This amount has become so important that it may trigger a snowball e

Following a request from Robin des Bois, an interview took place on January 14,2011 at the ESA offices in Paris between the three members of the NGO and sevenmembers of ESA. Three were physically present and four attended viavideoconference from the Kourou launch center in French Guiana - including theATv2 program director - and the European Space Research and Technology Centre(ES